python爬虫爬取有道翻译

import urllib.request
import urllib.parse
import json
import time

while True:
    content = str(input("请输入需要翻译的内容(输入'quit!'退出):"))
    if content =='quit!':
        print("感谢使用")
        break
    


    url='http://fanyi.youdao.com/translate?smartresult=dict&smartresult=rule'
    data={

    'i': content,
    'from': 'AUTO',
    'to': 'AUTO',
    'smartresult': 'dict',
    'client': 'fanyideskweb',
    'salt': '15837372097486',
    'sign': '8b1c0f6b6654975dcd9f89bb92d2b446',
    'ts': '1583737209748',
    'bv': 'ec579abcd509567b8d56407a80835950',
    'doctype': 'json',
    'version': '2.1',
    'keyfrom': 'fanyi.web',
    'action': 'FY_BY_CLICKBUTTION'
    }
    data = urllib.parse.urlencode(data).encode('utf-8')#编码


    req = urllib.request.Request(url,data)
    #伪装
    req.add_header('User-Agent','Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.25 Safari/537.36 Core/1.70.3741.400 QQBrowser/10.5.3863.400')

    response= urllib.request.urlopen(req)


    html= response.read().decode('utf-8')#解码

    #json.loads()将json字符串转发成为字典，提取数据，打印
    a = json.loads(html)
    target=a['translateResult'][0][0]['tgt']
    print(target)
    time.sleep(3)